WASHINGTON (AP) _ Legislation that would allow banks, securities firms and insurers to get further into each other's businesses has cleared the House after 20 years of failed efforts. But the bill's one-vote margin and the threat of a presidential veto make its prospects in the Senate clouded.

The 214-213 tally Wednesday night came after a daylong debate and a nail-biting last few minutes in which several lawmakers switched their votes and the total seesawed between approval and rejection. Some lawmakers paced the floor of the chamber, holding red and green electronic voting cards, one in each hand.

``We went to some people,'' Rep. John Boehner of Ohio, one of the House Republican leaders, told reporters afterward. ``There's no question that some (Republican) members who would rather have voted no, voted yes to move the bill.''

Similar legislation in the Senate has not been acted upon and the narrow vote in the House makes its prospects unclear. Sen. Alfonse D'Amato, R-N.Y., chairman of the Senate Banking Committee, has said the House would have to show broad bipartisan support for the legislation before his panel would act on it.

The Clinton administration, which contends the far-reaching bill would favor big bank-holding companies at the expense of small banks, renewed its veto threat on Wednesday. The measure also has been bitterly opposed by consumer activists, including Ralph Nader, and most of the banking industry.

Republican leaders who had thrown their prestige behind the bill only to have an embarrassing retreat forced on them six weeks ago were exulting after the vote.

``There goes the do-nothing Congress,'' said House Appropriations Committee Chairman Bob Livingston, R-La.

Underlining the high stakes for the Republicans, Democratic Rep. Barney Frank of Massachusetts said, ``The embarrassment of one more defeat would have been too much for them.''

The complex legislation spurred a barrage of lobbying by the financial industry in recent months and divided top federal regulators, the industry and each of the political parties. The banking industry on one side and the securities and insurance industries on the other have been pouring millions into the campaign coffers of key lawmakers.

Consumers Union said after the vote the package was a mixed blessing for the nation's consumers. While the bill would require banks to tell customers when financial products are not federally insured or when they involve potential risk of loss, the bill ``falls short'' of providing full consumer protection, the group said.

But proponents held out the promise of a globally competitive U.S. financial industry, with consumers benefiting from one-stop ``supermarkets'' catering to all their financial needs. The new structures would stretch ``from Wall Street to Main Street to Elm Street, from the cradle to the wedding to retirement,'' said Rep. Rick Lazio, R-N.Y.

David Komansky, chairman and chief executive officer of brokerage giant Merrill Lynch & Co., called the vote ``an historic breakthrough for American consumers and our nation's financial markets.''

The bill was boosted by a stunning new merger of banking giant Citicorp and brokerage-insurer Travelers Group, part of a recent outbreak of merger mania in various industries. The deal, valuing each company at $69 billion, put added pressure on Congress to revamp the nation's financial services laws.

The Federal Reserve could allow the two financial powerhouses to operate as one under current laws for up to five years, requiring some businesses to be sold off. Congress is widely expected to have enacted some kind of overhauling of banking law by then.

Earlier Wednesday, with the Democrats evenly divided, the House defeated an effort to allow banks to get into new businesses through their existing divisions. A 306-115 vote rejected an amendment by Rep. John LaFalce of New York, senior Democrat on the Banking Committee, that he contended would have helped smaller banks diversify in an intensely competitive marketplace.

Rejection of the amendment appeared to dim prospects for a softening of White House opposition to the bill.

Republican leaders, facing GOP defections as well as Democratic opposition, abruptly withdrew an earlier version of the bill before a scheduled vote six weeks ago.